U.S. patent application number 13/395667 was filed with the patent office on 2012-08-30 for semiconductor luminaire.
This patent application is currently assigned to OSRAM OPTO SEMICONDUCTORS GMBH. Invention is credited to Christopher L. Eichelberger, Kimberly Peiler.
Application Number | 20120218773 13/395667 |
Document ID | / |
Family ID | 43796110 |
Filed Date | 2012-08-30 |
United States Patent
Application |
20120218773 |
Kind Code |
A1 |
Peiler; Kimberly ; et
al. |
August 30, 2012 |
SEMICONDUCTOR LUMINAIRE
Abstract
A semiconductor luminaire includes a carrier; an optoelectronic
semiconductor chip mounted on the carrier, the semiconductor chip
emitting ultraviolet or visible radiation; a luminaire housing not
covering the semiconductor chip in a direction of main emittance;
an optical cover placed downstream of the semiconductor chip in a
direction of mails emittance: and an index matching layer located
between the semiconductor chip mid the optical cover, wherein the
optical cover provides a radiation exit surface of the luminaire,
and wherein radiation running along the direction of main emittance
from the semiconductor chip to the radiation exit surface solely
propagates in solid or liquid materials.
Inventors: |
Peiler; Kimberly;
(Northville, MI) ; Eichelberger; Christopher L.;
(Livonia, MI) |
Assignee: |
OSRAM OPTO SEMICONDUCTORS
GMBH
Regensburg
DE
|
Family ID: |
43796110 |
Appl. No.: |
13/395667 |
Filed: |
September 25, 2009 |
PCT Filed: |
September 25, 2009 |
PCT NO: |
PCT/US09/58309 |
371 Date: |
May 15, 2012 |
Current U.S.
Class: |
362/520 ;
362/235; 362/240; 362/294; 362/311.06; 362/311.14 |
Current CPC
Class: |
F21Y 2115/10 20160801;
F21V 15/01 20130101; F21S 45/47 20180101; F21V 5/04 20130101; F21V
29/763 20150115; F21V 31/005 20130101; G02B 3/0056 20130101; H01L
33/58 20130101; F21S 45/50 20180101; G02B 3/04 20130101; F21S
41/143 20180101; F21V 29/76 20150115; F21S 41/153 20180101; H01L
33/56 20130101 |
Class at
Publication: |
362/520 ;
362/311.14; 362/311.06; 362/294; 362/235; 362/240 |
International
Class: |
B60Q 1/04 20060101
B60Q001/04; F21V 5/04 20060101 F21V005/04; F21V 29/00 20060101
F21V029/00; F21V 5/00 20060101 F21V005/00 |
Claims
1. A semiconductor luminaire comprising: a carrier; an
optoelectronic semiconductor chip mounted on the carrier, the
semiconductor chip emitting ultraviolet or visible radiation; a
luminaire housing not covering the semiconductor chip in a
direction of main emittance; an optical cover placed downstream of
the semiconductor chip in a direction of main emittance; and an
index matching layer located between the semiconductor chip and the
optical cover, wherein the optical cover provides a radiation exit
surface of the luminaire, and wherein radiation running along the
direction of main emittance from the semiconductor chip to the
radiation exit surface solely propagates in solid or liquid
materials,
2. The semiconductor luminaire according to claim 1, wherein the
optical cover is shaped lens-like at least in parts.
3. The semiconductor luminaire according to claim 1, further
comprising a heat sink wherein the carrier is directly provided on
the heat sink.
4. The semiconductor luminaire according to claim 1, wherein the
optical cover comprises a flange, the optical cover being fixed to
the carrier by the luminaire housing and by the flange.
5. The semiconductor luminaire according to claim 1, further
comprising a gasket, the gasket located between the optical cover
and the luminaire housing to seal the carrier and the semiconductor
chip against ambient conditions.
6. The semiconductor luminaire according to claim 5, wherein the
gasket, the luminaire housing and the optical cover overlap in a
lateral direction.
7. The semiconductor luminaire according to claim 1, wherein the
semiconductor chip is directly mounted onto the carrier, the
carrier being one item selected from the group consisting of a
circuit board, a printed circuit board, a ceramic and a metal core
substrate.
8. The semiconductor luminaire according to claim 1, further
comprising a chip housing which the semiconductor chip is placed
in, the chip housing being directly mounted onto the carrier.
9. The semiconductor luminaire according: to claim 1, comprising a
plurality of semiconductor chips, all semiconductor chips being
covered by the optical cover, and the optical cover being
one-pieced.
10. The semiconductor luminaire according to claim 1, wherein the
optical cover comprises a lens array, each lens and each
semiconductor chip being assigned one-to-one to each other.
11. The semiconductor luminaire according to claim 1, comprising a
plurality of semiconductor chips and a plurality of optical covers,
the optical covers being disposed on the carrier and displaced in a
lateral direction and fixed by means of the luminaire housing, each
optical cover being assigned to one or more semiconductor
chips.
12. The semiconductor luminaire according to claim 1, wherein the
radiation exit surface of the optical cover is flush with an outer
surface of the luminaire housing.
13. The semiconductor luminaire according to claim 1, wherein the
semiconductor chip is located in a recess of the optical cover.
14. A vehicular headlamp comprising the semiconductor luminaire
according to claim 1.
Description
RELATED APPLICATIONS
[0001] This is a .sctn.371 of International Application No.
PCT/US2009/058309, with an inter-national filing date of Sep. 25,
2009 (WO 2011/037571 A1, published Mar. 31, 2011), the subject
matter of which is incorporated by reference.
TECHNICAL FIELD
[0002] This disclosure relates to semiconductor luminaires,
particularly to semiconductor luminaires which have a high light
out-coupling efficiency.
SUMMARY
[0003] Provided are semiconductor luminaires including a carrier;
an optoelectronic semiconductor chip mounted on the carrier, the
semiconductor chip emitting ultraviolet or visible radiation; a
luminaire housing not covering the semiconductor chip in a
direction of main emittance; an optical cover placed downstream of
the semiconductor chip in a direction of main emittance; and an
index matching layer located between the semiconductor chip and the
optical cover, wherein the optical cover provides a radiation exit
surface of the luminaire, and wherein radiation running along the
direction of main emittance from the semiconductor chip to the
radiation exit surface solely propagates in solid or liquid
materials.
[0004] Also provided are vehicular headlamps including the
semiconductor luminaires.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] Advantageous examples and developments of the semiconductor
luminaire and the vehicular headlamp will become apparent from the
representative examples described below in association with the
figures.
[0006] FIG. 1A is a schematic sectional view of a semiconductor
luminaire.
[0007] FIG. 1B is an exploded schematic sectional view of a portion
of the semiconductor luminaire of FIG. 1A.
[0008] FIG. 2 is a schematic sectional view of another luminaire
with one semiconductor chip.
[0009] FIG. 3 is a schematic sectional view of another luminaire
with two semiconductor chips.
[0010] FIG. 4 is a schematic sectional view of yet another
semiconductor luminaire.
[0011] FIG. 5 is a schematic sectional view of a portion of another
semiconductor luminaire.
[0012] FIG. 6A is a schematic sectional view of yet another
semiconductor luminaire.
[0013] FIG. 6B is a top view of the semiconductor luminaire of FIG.
6A.
[0014] FIG. 7A is a schematic sectional view of a portion of a
semiconductor luminaire comprising a plurality of optoelectronic
semiconductor chips.
[0015] FIG. 7B is a top view of the semiconductor luminaire of FIG.
7A.
[0016] FIG. 7C is another top view of the semiconductor luminaire
of FIG. 7A.
[0017] FIG. 8A is a schematic sectional view of a semiconductor
luminaire with a plurality of semiconductor chips.
[0018] FIG. 8B is a top view of the semiconductor luminaire of FIG.
8A.
[0019] FIG. 9A is a schematic sectional view of a gasket and
optical cover in connection with a semiconductor luminaire.
[0020] FIG. 9B is a schematic sectional view of a multilayered
structure that may be used in accordance with the structure of FIG.
9A.
[0021] FIG. 10 is a schematic sectional view of still another
semiconductor luminaire.
[0022] FIG. 11 is a schematic sectional view of still a further
semiconductor luminaire.
DETAILED DESCRIPTION
[0023] The semiconductor luminaire may comprise a carrier. The
carrier provides mechanical stability for the semiconductor
luminaire. The carrier can also serve as an electrical connection
means. By way of example, the carrier can be a printed circuit
board, a circuit board, a metal core board, or a ceramic board with
conductor paths. Preferably, the carrier has a low thermal
resistance. For example, an average thermal conductivity of the
carrier is equal to or exceeds 40 W/(m K), especially 100 W/(m
K).
[0024] The semiconductor luminaire may comprise at least one
optoelectronic semiconductor chip. The semiconductor chip may be
mounted on the carrier and is capable of emitting ultraviolet or
visible radiation during operation of the luminaire. For example,
the semiconductor chip is a thin film chip with a thickness of at
most 200 .mu.m, especially of at most 20 .mu.m with regard to
epitaxially grown layers. The semiconductor chip can be formed as
described in WO 2005/081319 A1 or DE 10 2007 004 304 A1, of which
the disclosed content relating to the semiconductor chip is hereby
incorporated by reference. Especially, the semiconductor chip can
be a light-emitting diode or a laser diode or a super-luminescent
diode.
[0025] The semiconductor luminaire may further comprise a luminaire
housing. The housing does not in this instance cover the
semiconductor chip in a direction of main emittance. Particularly,
if the semiconductor chip shows a Lambertian radiation
characteristic, the direction of main emittance is essentially
perpendicular to a main surface of the semiconductor chip. In this
case, in a direction perpendicular to the main surface of the
semiconductor chip, there is no part of the luminaire housing. The
luminaire housing is preferably made from a material or comprises
such a material that is not transparent or translucent to the
electromagnetic radiation generated by the semiconductor chip. For
example, the luminaire housing comprises a sheet metal.
[0026] The semiconductor luminaire may comprise an optical cover.
In the direction of the main emittance of the semiconductor chip,
the optical cover may be placed downstream of the semiconductor
chip. In other words, a main part of the radiation generated by the
optoelectronic semiconductor chip runs to and preferably through
the optical cover. The optical cover can comprise or consist of a
glass, a plastic or the like. Suitable plastic materials are, for
example, polycarbonate, polymethylmetacrylate, a liquid crystal
polymer, an epoxy or an epoxy-silicon-hybrid material. Preferably,
the optical cover is fashioned to be transparent and/or see-through
for the radiation generated by the semiconductor chip or at least
for a part of this radiation.
[0027] An index matching layer may be located between the
semiconductor chip and the optical cover. The index matching
material consists of a liquid or, preferably, of a solid. Also
preferably, the index matching layer may be made from a material
being see-through with regard to the radiation or at least with
regard to a part of the radiation generated by the semiconductor
chip in service of the luminaire.
[0028] The index matching layer may be in direct contact with the
optical cover. In other words, the material of the index matching
layer touches a material of the optical cover.
[0029] The index matching layer may have an optical refractive
index between 1.4 and 1.9, especially between 1.55 and 1.8,
inclusive. Especially, the optical refractive index of the material
of the index matching layer is between the refractive index of the
semiconductor chip and of the optical cover.
[0030] The optical cover may provide a radiation exit surface of
the semiconductor luminaire. In other words, a surface of the
semiconductor luminaire by which the radiation generated by the
semiconductor chip leaves the luminaire is comprised by the optical
cover. Thus, the radiation exit surface of the optical cover also
is an outer surface of the whole semiconductor luminaire.
[0031] The radiation running along the direction of main emittance
from the semiconductor chip to the radiation exit surface may
solely propagate in solid or liquid materials. Preferably, all
radiation emitted at the radiation exit surface of the optical
cover solely runs in solid materials from the semiconductor chip to
the radiation exit surface. In other words, there is especially no
air gap in-between the semiconductor chip and the radiation exit
surface, at least in the direction of main emittance. Because of
that, the radiation emitted by the semiconductor chip does not have
to run through boundary surfaces that are defined by a rapid,
step-like jump in the optical refractive index. Because of that,
the radiation out-coupling efficiency is increased.
[0032] The semiconductor luminaire may comprise a carrier and an
optoelectronic semiconductor chip mounted on the carrier. In
service of the semiconductor luminaire, the semiconductor chip is
suited to emit an ultraviolet and/or a visible radiation. The
semiconductor luminaire may further comprise a luminaire housing,
the luminaire housing not covering the semiconductor chip in a
direction of main emittance. Moreover, the semiconductor luminaire
may comprise an optical cover that is placed downstream of the
semiconductor chip seen in the direction of main emittance.
Furthermore, the semiconductor luminaire may include an index
matching layer that is located between the semiconductor chip and
the optical cover. Thereby, the optical cover provides a radiation
exit surface of the luminaire. Also, the radiation running along
the direction of main emittance from the semiconductor chip to the
radiation exit surface solely propagates in solid and/or liquid
materials.
[0033] The optical cover may be shaped lens-like, at least in
places. Hence, by means of the optical cover, a radiation profile
of the radiation emitted by the semiconductor luminaire can be
formed in a pre-defined manner. For example, the optical cover
collimates the radiation generated by the semiconductor chip.
[0034] The semiconductor luminaire may further comprise a heat
sink. The heat sink can be a passive one or an active one. For
example, the heat sink comprises cooling fins. It is also possible
that the heat sink comprises a thermal-electrical element, for
instance a Peltier element, or a fan. Also, a cooling effect by the
circulation of a gas or a liquid could be realized by the heat
sink.
[0035] The carrier may be a printed circuit board that is directly
provided on the heat sink. That the carrier is directly provided on
the heat sink can mean that there is only an adhesive like a solder
in between the carrier and the heat sink. Because of that, a low
thermal resistance in between the carrier and the heat sink can be
realized. Hence, an efficient cooling of the optoelectronic
semiconductor chip can be performed through the heat sink.
[0036] The optical cover may comprise a flange. The flange is, for
instance, a pedestal-like structure that in a lateral direction at
least partially surrounds the lens-like part of the optical
cover.
[0037] The optical cover may be fixed to the semiconductor
luminaire by means of the luminaire housing and by means of the
flange. In other words, the flange can be pressed, for example, to
the carrier by a distinct part of the luminaire housing.
[0038] A gasket that is comprised by the semiconductor luminaire
may be located between the optical cover and the luminaire housing
to seal the carrier and the semiconductor chip, especially against
dust, humidity and water. Preferably, the gasket is in direct
contact both with the optical cover and the luminaire housing. The
gasket can comprise or consist of, for instance, a rubber and/or a
silicon.
[0039] The gasket, the luminaire housing and the optical cover may
overlap in a lateral direction. In other words, there may be a
straight line oriented in parallel with the direction of main
emittance that crosses that gasket as well as the luminaire housing
and as the optical cover.
[0040] The semiconductor chip may be mounted directly onto the
carrier. In other words, in between the semiconductor chip and the
carrier, there is at most an adhesive like a solder or an
electrically conductive glue. Preferably, there are no other parts
between the semiconductor chip and the carrier, especially no
materials like plastics that have a low thermal conductivity.
[0041] The semiconductor luminaire may further comprise a chip
housing, wherein the semiconductor chip is placed in the chip
housing. The housing can comprise a lead frame and a plastics
material as well as a casting material.
[0042] The chip housing may be mounted directly onto the carrier in
such a way that, preferably, there is only an adhesive in between
the chip housing or parts of the chip housing and the carrier. An
adhesive in this sense is also a heat-conductive paste that is
arranged in between parts of the chip housing and the carrier.
Especially, the chip housing comprises a thermal socket on which
the semiconductor chip is mounted, the socket being thermally
contacted to the carrier by the heat-conductive paste.
[0043] The semiconductor luminaire may comprise a plurality of
semiconductor chips wherein all semiconductor chips are covered by
the optical cover. Especially, in directions perpendicular to the
main surfaces of the semiconductor chips, the semiconductor chips
are followed by the optical cover. Thus, a main part of the
radiation generated by the semiconductor chips travels through the
optical cover.
[0044] The optical cover may be one-pieced. In this case, it is
possible that the semiconductor luminaire comprises exactly one
optical cover.
[0045] The optical cover may comprise a lens array. The lens array
is especially integrally formed with the optical cover. Thus, the
optical cover and lens array are formed in one piece.
[0046] Each lens of the lens array of the optical cover and each
semiconductor chip may be assigned in a one-to-one manner with
respect to each other. Thus, the number of semiconductor chips may
also be equal to the number of lenses of the lens array.
[0047] The semiconductor luminaire may comprise a plurality of
semiconductor chips and a plurality of optical covers, wherein the
optical covers are disposed on the carrier and displaced in a
lateral direction. Preferably, each optical cover is assigned to
one or more semiconductor chips. In this case, the semiconductor
luminaire comprises more optoelectronic semiconductor chips than
optical covers.
[0048] The radiation exit surface of the optical cover may be flush
with an outer surface of the luminaire housing. This enables an
especially flat design of the semiconductor luminaire.
[0049] The semiconductor chip may be located in a recess of the
optical cover. Especially, the semiconductor chip may be completely
surrounded by the optical cover and the carrier and eventually also
by an adhesive that locks the optical cover and the carrier to each
other.
[0050] Furthermore, a vehicular headlamp is provided. The headlamp
is especially suited for use in a motor vehicle such as cars or
trucks. Especially, the vehicular headlamp comprises one or more
luminaires according to one of the preceding forms. Thus, the
subject matter disclosed for the semiconductor luminaire is also
disclosed for the vehicular headlamp and vice-versa.
[0051] In the representative examples and figures, similar or
similarly acting constituent parts are provided with the same
reference symbols. The elements illustrated in the figures and
their size relationships among one another should not be regarded
as true to scale. Rather, individual elements may be represented
with an exaggerated size for the sake of better representability
and/or for the sake of better understanding.
[0052] In FIG. 1A, an exemplary form of a semiconductor luminaire 1
is shown in a sectional view. The semiconductor luminaire 1 that
can be a vehicular headlamp comprises an optical cover 6, shown in
more detail in the sectional view in FIG. 1B. The semiconductor
luminaire 1 further comprises a heat sink 9 with a top face 90 and
with cooling fins 95 remote from the top face 90. A carrier 2 is
arranged on the top face 90. As an example, the carrier 2 is a
printed circuit board, a metal core board or a ceramic, equipped
with conductive paths on a main area 20 of the carrier 2, the main
area 20 being remote from the heat sink 9.
[0053] By means of an adhesive 11, an optoelectronic semiconductor
chip 3 is mounted on the main area 20 of the carrier 2. The
adhesive 11 is, for instance, a solder. In service of the
semiconductor luminaire 1, the semiconductor chip 3 is suited to
emit visible and/or ultraviolet radiation in a direction M of main
emittance, indicated by an arrow. As an example, the direction M of
main emittance is oriented essentially perpendicular with respect
to the main area 20 of the carrier 2. The main area 20 could be
made reflective for the radiation. In a variant, not shown in the
figures, the direction of main emittance is deflected by, for
instance, an additional mirror that follows the semiconductor
chip.
[0054] Further, the semiconductor chip 3 is surrounded on surfaces
that do not face the carrier 2 with an index matching layer 7. The
semiconductor chip 3 is completely surrounded by the index matching
layer 7 and the carrier 2. The index matching layer 7 is roughly
shaped in the form of a hemisphere.
[0055] A luminescence conversion material 15 in the form of a layer
is attached on a surface of the semiconductor chip 3 remote from
the carrier 2. The luminescence conversion material 15 absorbs at
least part of the radiation emitted by the semiconductor chip 3 and
converts this radiation to a radiation with another wavelength.
Thus, the radiation emitted by the semiconductor luminaire 1 can be
white light that comprises radiation originally emitted by the
semiconductor chip 3 mixed with radiation generated by conversion
in the conversion luminescence material 15. The conversion
luminescence material 15 can be present in all figures, although
not drawn explicitly.
[0056] Moreover, the optical cover 6 comprises a lens part 61 and
flanges 62. In the lens part 61, the optical cover 6 is shaped
lens-like. Via the lens part 61, a radiation characteristic of the
radiation emitted by the semiconductor chip 3 and by the
luminescence conversion material 15 can be formed. Further, the
optical cover 6 comprises a recess 65 in which the semiconductor
chip 3 and the index matching layer 7 are arranged. An inner
surface 64 of the recess 65 is in direct contact with the index
matching layer 7.
[0057] Via the flanges 62 that can partially or completely surround
the lens part 61 in a lateral direction, the optical cover 6 is
fixed to the carrier 2 and the heat sink 9 by a gasket 8 and a
luminaire housing 5. In a direction parallel to the direction M of
main emittance, the flanges 62 of the optical cover 6, the gasket 8
and a part of the luminaire housing 5 are stacked one above the
other. Hence, the optical cover 6 is pressed through the gasket and
the luminaire housing onto the carrier 2. By means of the gasket 8,
the semiconductor chip 3, as well as the carrier 2, are sealed
against dust, water and/or humidity. Thus, the gasket 8 is in
direct contact both with the luminaire housing 5 and the flanges 62
of the optical cover 6.
[0058] A radiation exit surface 16 of the semiconductor luminaire 1
is formed by the optical cover 6. Thus, the radiation from the
semiconductor chip 3 only runs in solid materials from the
semiconductor chip 3 to the radiation exit surface 60. Hence, the
radiation exit surface 60 of the optical cover 6 is also an outer
surface of the semiconductor luminaire 1.
[0059] The luminaire housing 5 has an outer surface 50. The
luminaire housing 5 further comprises an opening 55 in which at
least the lens part 61 of the optical cover 6 is arranged.
Especially, the outer surface 50 of the luminaire housing is flush
with the radiation exit surface 60 of the optical cover 6.
[0060] In FIG. 2, an example of another luminaire with one
semiconductor chip 3 is illustrated. The chip 3 is located in a
chip housing 4. Thus, the chip 3 is not in direct contact with the
carrier 2. Furthermore, there is an air gap 13 in between the chip
3 and a lens 16. The lens 16 is fixed to the carrier 2 by two
holders 12. A further air gap 13 is present between the lens 16 and
the luminaire housing 5 that is transparent to the radiation
emitted by the semiconductor chip 3. The housing 5 forms an outer
surface 50 of the luminaire as well as a radiation exit surface 50.
Also, the chip 3 is covered by the housing 5 in a direction
parallel to the direction M of main emittance of the radiation
generated by the chip.
[0061] Due to the air gaps 13, there is a relatively large
discontinuity with regard to the optical refractive index in
between the chip 3 and the air gap, in between the two air gaps 13
and the lens 16 as well as in between the air gap 13 remote from
the carrier 2 and the housing 5. On each boundary surface of these
air gaps, due to the jump in the optical refractive index, about 5%
of the radiation is reflected back to the carrier 2 and/or the chip
3. Thus, due to the two air gaps 13, a light-out-coupling
efficiency of the luminaire according to FIG. 2 is reduced by
roughly 10%. This loss of about 10% is not present in the selected
structures such as, for example, in the semiconductor luminaire 1
as depicted in FIG. 1. Thus, the efficiency of the semiconductor
luminaire 1 according to FIG. 1, for instance, is increased.
[0062] In FIG. 3, another luminaire with two semiconductor chips 3
is illustrated. According to FIG. 3, there is also an air gap 13
between an optical cover 6 and a lens 16. Due to this air gap, a
light out-coupling efficiency of the device according to FIG. 3 is
reduced by about 5% compared with the semiconductor luminaire 1 as
depicted in FIG. 1. There may also be an air gap between the lenses
16 and the semiconductor chips 3 that could further reduce the
efficiency of the luminaire.
[0063] Furthermore, there is a comparably large thermal resistance
due to the housing, the carrier 2 and the adhesive 11 in between
the semiconductor chip 3 and the heat sink 9. Thus, a performance
with regard to thermal aspects of the luminaire according to FIG. 3
is decreased. As the semiconductor chip 3 according to FIG. 1 is
mounted directly on the carrier and the carrier 2 is in direct
contact with the heat sink 90, heat transfer from the semiconductor
chip 3 to the heat sink 9 is increased.
[0064] FIG. 4 shows another example of a semiconductor luminaire 1.
In contrast to the structure of FIG. 1, the semiconductor chip 3 is
arranged in the chip housing 4, for example, made from a silicone,
a silicone-epoxy-hybrid material, an epoxy or the like. The chip
housing 4 is shaped lens-like and can serve to decrease an angle of
emittance of the radiation generated by the semiconductor chip
3.
[0065] The semiconductor luminaire 1 can be used in a vehicular
headlamp as well as all other examples such as in FIGS. 5 to 11. In
this case, a radiation characteristic of the radiation emitted by
the semiconductor luminaire 1 preferably is asymmetric to fulfill
the requirements of a headlamp, for example, for a car.
[0066] In the examples as depicted in FIG. 5, the optical cover 6
comprises a plurality of lens parts 61, each formed as a microlens.
The lens parts 61 of the optical cover 6 can be formed similarly.
Alternatively, it is also possible that the lens parts 61 differ
from each other to form, for instance, a Fresnel lens-like optical
cover 6.
[0067] The semiconductor chip 3 is, as well as in FIG. 4, arranged
in the chip housing 4. Via the chip housing 4, the radiation
emitted by the semiconductor chip 3 is collected and led into the
direction M of main emittance with a high efficiency. Due to the
forming of a plurality of lens parts 61 in the optical cover 6, the
semiconductor luminaire 1 can be formed to be very flat and
volume-saving.
[0068] Now, referring to the example according to FIG. 6, such as
in the sectional view of FIG. 6A and the top view in FIG. 6B, the
semiconductor luminaire comprises a plurality of semiconductor
chips 3 and also a plurality of optical covers 6. Each
semiconductor chip 3 is assigned to exactly one of the optical
covers 6 and vice-versa. Each of the optical covers 6 is fixed to
the carrier 2 by means of the gaskets 8 and the one-pieced
luminaire housing 5. Thus, a semiconductor luminaire 1 with a high
luminosity can be achieved.
[0069] According to FIG. 7, such as in the sectional view in FIG.
7A and top views in FIGS. 7B and 7C, the semiconductor luminaire 1
comprises a plurality of optoelectronic semiconductor chips 3 and
the optical cover 6 comprises a lens array with a plurality of lens
parts 61. Each lens part 61 is assigned to one of the semiconductor
chips 3. The carrier 2 is located in a recess of the heat sink 9.
Thus, the main area 20 of the carrier 2 is flush with the top face
90 of the heat sink 9.
[0070] As shown in FIG. 7C, the optical cover 6 is one piece
comprising the plurality of lens parts. As an alternative, the
semiconductor luminaire 1 according to FIG. 7B comprises more
optical covers 6, each of these optical covers 6 comprising, for
example, four lens parts 61. Thus, in both cases the lens parts 61
are arranged in an array-like structure.
[0071] In contrast to the examples according to FIGS. 1 and 4 to 6,
according to FIG. 7, the optical cover 6 projects over the carrier
2 in a lateral direction. Thus, in a direction parallel to the
direction M of main emittance, the heat sink 9, the optical cover
6, the gasket 8 and the luminaire housing 5 are in subsequent
direct contact with each other. By lateral projection of the
optical cover 6 over the carrier 2, by fixing the optical cover 6
with the heat sink 9, the carrier 2 is mechanically
disburdened.
[0072] According to FIG. 8, the sectional view in FIG. 8A and the
top view in FIG. 8B, the plurality of semiconductor chips 3 is
arranged in one common recess 65 of the optical cover 6. The
luminaire housing 5 is shaped U-like to clasp the optical cover 6
and the carrier 2 with the heat sink 9. Between a holding part 52
of the luminaire housing 5 and the heat sink 9, an additional
sealing member 14 can be optionally provided to fully seal the
semiconductor chips 3 and the carrier 2 from the
environment/ambient conditions.
[0073] For the sake of simplifying the graphical representation, in
FIG. 8B an arrangement of two times two semiconductors chips 3 is
shown, deviating from the illustration of FIG. 8A.
[0074] According to the sectional view in FIG. 9A, the gasket 8 is
flush with the optical cover 6 in a lateral direction perpendicular
to the direction M of the main emittance of the semiconductor chip
3.
[0075] According to the sectional view in FIG. 9B, the carrier 2
can be a multi-layered structure comprising a dielectric layer 21,
an electrically conductive layer 22 and a mask layer 23. The
dielectric layer 21, for example, consists of or comprises a
ceramic or a plastic. Preferably, the thermal resistance of the
dielectric layer 21 is negligible. The electrically conductive
layer 22 is, for instance, a copper layer. The mask layer 23 can be
a layer of a structured solder. For example, the mask layer 23 is
only present in regions where electrical contacts of the
semiconductor chip 3 are applied to the carrier 2. An overall
thickness of the carrier 2 can be between 100 .mu.m and 2 mm,
inclusive, preferably between 300 .mu.m and 1 mm, inclusive.
[0076] The carrier 2 according to the examples as shown in FIG. 10
comprises adjustor or adjustment means 25. Via the adjustment means
25, which have inclined lateral faces facing the optical cover 6,
the optical cover 6 that also can have inclined lateral faces can
be adjusted in a simple way and accurately with respect to the
carrier 2.
[0077] The semiconductor chip 3 is, for example, arranged in a
housing 4. Especially, the semiconductor chip 3 can be arranged on
a socket 17 made of a thermally highly conductive material that is
in thermal contact with the carrier 2, for instance by means of a
thermal conductive paste.
[0078] It is possible that the chip housing 4 is soldered to the
carrier 2 before the optical cover 6 is mounted. Either for filling
the recess 65 with the material for the index matching layer 7 or
to enable a release of air that otherwise would be trapped in the
recess 65, the optical cover 6 optionally could comprise a duct 66
on a lateral surface of the lens-like part 61. Such a duct can also
be provided in the optical covers of all examples.
[0079] Diverging from FIG. 10, the duct 66 could also be covered by
the gasket 8 for better sealing of the duct 66. As in all other
examples, the optical cover 6 can protrude from the outer surface
50 of the luminaire housing 5.
[0080] Another example is illustrated in FIG. 11. In this form, the
carrier 2 is flush with the optical cover 6 to simplify mounting of
the semiconductor luminaire 1. Lateral surfaces of the opening 55
in the luminaire housing 5 are tapered. Furthermore, the gasket 8
is fixed to a side of the luminaire housing 5 facing the heat sink
9. Thus, during the mounting of the semiconductor luminaire 1, the
gasket 8 and the luminaire housing 5 can be regarded as being one
piece. Due to the tapered lateral surfaces of the opening 55, a
space in between the luminaire housing 5 and the optical cover 6 in
a lateral direction near the outer surface 50 and the radiation
exit surface 60, respectively, can be minimized. In this form, the
gasket 8 projects in a lateral direction over the optical cover 6
and the carrier 2.
[0081] This disclosure is not restricted to the representative
examples by the description on the basis of those examples. Rather,
the disclosure encompasses any new feature and also any combination
of features, which in particular comprises any combination of
features in the claims and any combination of features in the
examples, even if this feature or this combination itself is not
explicitly specified in the claims or examples.
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